define one standard kg
Answer:
The mass of platinum iridium rod whose diameter and height are equal an kept at international bureau of weight and measurement in Paris of France is called as one standard kg.
an athlete had lifts a load with a mass of 150kg.
1) calculate the gravitational potential energy gained
2) if the mass of the load is increased to 200kg, calculate the gravitational potential energy gained by the load.
3) based on answers in 1&2, state the relationship between the mass of the load and the gravitational potential energy.
[tex]\\ \sf\longmapsto P.E=mgh[/tex]
[tex]\\ \sf\longmapsto P.E=150(2)(10)[/tex]
[tex]\\ \sf\longmapsto P.E=3000J[/tex]
In 2nd case
Mass =m=200kgHeight=h=2mg=10m/s^2[tex]\\ \sf\longmapsto P.E=200(2)(10)[/tex]
[tex]\\ \sf\longmapsto P.E=4000J[/tex]
We can observe that
If mass of body increases gravitational potential energy will increase.A tray containing 0.20kg of water at 20degree celsius is placed in a freezer. The temperature of the water drops to 0degree celsius in 10 minutes. Calculate
a) The energy lost by the water asit cools to 0 degree celsius.
b) The average rate at which the water is losing energy in J/s.
c) Estimate the time taken for the water at 0 degree celsius to turn completely into ice.
d) state any assumptios you make
Answer:
a. Energy lost, Q = 16,800 Joules.
b. Power = 28 J/s
c. Time, t = 2357.14 seconds
d. I assumed that the ice remained at a temperature of zero degrees Celsius (0°C). Also, I assumed that the heat is being lost at a constant rate.
Explanation:
Given the following data;
Mass = 0.20 kgInitial temperature, T1 = 20°CFinal temperature = 0°CTime = 10 minutesa. To find the energy lost by the water as it cools to 0 degree celsius;
Mathematically, heat capacity is given by the formula;
[tex] Q = mcdt [/tex]
Where;
Q represents the heat capacity or quantity of heat.M represents the mass of an object.C represents the specific heat capacity of water.dt represents the change in temperature.dt = T2 - T1
dt = 20 - 0
dt = 20°C
We know that the specific heat capacity of water is equal to 4200 J/kg°C
Substituting the values into the formula, we have;
[tex] Q = 0.20 * 4200 * 20 [/tex]
Energy lost, Q = 16,800 Joules.
b. To find the average rate at which the water is losing energy in J/s by using the following formula;
[tex] Power = \frac {energy}{time} [/tex]
First of all, we would have to convert the value of time in minutes to seconds.
Conversion:
1 minute = 60 seconds
10 minutes = X seconds
Cross-multiplying, we have;
X = 60 * 10
X = 600 seconds
Substituting the values into the formula, we have;
[tex] Power = \frac {16800}{600} [/tex]
Power = 28 J/s
c. To estimate the time taken for the water at 0 degree celsius to turn completely into ice;
We know that the latent heat of fusion of water is equal to 3.3 * 10⁵ J/kg.
Mathematically, the latent heat of fusion is calculated by using the formula;
Energy, Q = ml = pt
Substituting the values into the formula, we have;
0.20 * 3.3 * 10⁵ = 28 * t
0.20 * 330000 = 28t
66000 = 28t
[tex] t = \frac {66000}{28} [/tex]
Time, t = 2357.14 seconds.
d. The assumption made is that, the ice remained at a temperature of zero degrees Celsius (0°C). Also, I assumed that the heat is being lost at a constant rate.
A certain superconducting magnet in the form of a solenoid of length 0.28 m can generate a magnetic field of 7.0 T in its core when its coils carry a current of 80 A. The windings, made of a niobium-titanium alloy, must be cooled to 4.2 K. Find the number of turns in the solenoid.
Answer:
The number of turns in the solenoid is 19506.
Explanation:
Length of solenoid, L = 0.28 m
Magnetic field, B = 7 T
Current, I = 80 A
Let the number of turns is N.
The formula used to find the magnetic field is
[tex]B = \frac{\mu 0N I}{L}\\\\7 = \frac{4 \times 3.14\times 10^{-7}\times N\times 80}{0.28}\\\\N = 19506[/tex]
Solve the following numerical problems. a) A load of 400N is lifted up by an effort of 100N. If load distance is 20cm, what will be the effort distance? (Ans: 80cm) b) Two boys, Shrijan having weight 600N and Shrijesh having weight 300N are playing see-saw. If Shrijan is sitting at 2m from fulcrum, where should Shrijesh sit from fulcrum to balance Shrijan?(Ans: 4m) c) A lever of length 1m has been used ttoko lift a load of 600N by applying an effort of 200N. If load is at 20cm from fulcrum, calculate mechanical advantage, velocity ratio and efficiency. (Ans: MA = 3, VR = 4, n=75%) d) Study the figure below and find the value of effort. (Ans: 120N) Muyn) 2.5m 600N 0.5m ? Science and Enyin
Answer:
given,
load = 400 N
effort = 100 N
load distance = 20 cm
we know that ,
E*Ed = L*Ld
=100 N* Ed = 400N * 20 cm
=100N * Ed = 8000N/cm
= Ed =( 8000N/cm ) / 100N
= Ed = 80 cm
b. soln.
given,
load = 600 N
load distance = 2 m
effort = 300 N
effort distance = ?
we know that ,
= E *Ed = L * Ld
= 300N * Ed = 600N * 2 m
= 300N * Ed = 1200N/m
=Ed =( 1200N/m ) / 300 N
= Ed = 4 m
C. soln.
given,
load = 600 N
load distance =20 cm
effort = 200 N
effort distance = ?
M.A = ?
V.R = ?
Efficiency = ?
we know that ,
= E *Ed = L *Ld
= 200N * Ed = 600 N * 20 cm
=200 N *Ed = 12000 N/cm
=Ed = ( 12000 N/cm) / 200 N
= Ed = 60 cm
Also,
M.A = load / effort
=600 N / 200 N
= 3
V.R = Ed/ Ld
= 60 cm / 20 cm
= 4
efficiency = ( M.A / V.R ) 100 %
= ( 3 / 4 ) 100%
= 75 %
d. soln.
given,
load = 600 N
load distance = 0.5 m
effort distance = 2.5 m
effort = ?
we know that ,
= E * Ed = L * Ld
= E * 2.5 m = 600 N * 0.5 m
= E * 2.5 m = 300 N / m
= E = ( 300 N / m ) / 2.5 m
= E = 120 N
Thiết bị nào sau đây không phải là nguồn điện
A. Ắc quy
B. Pin
C. Máy phát điện
D. Bóng đèn điện
300 ml of a gas at 27°C is Cooled at -3°c at Constant pressure the final volume is plzz answer fast i will mark brainliest
Answer:V₁=300ml
T₁=27°C
V₂=?
T₂= -3°C
as we know
V₁T₁=V₂T₂
By putting values in formula
300ml×27°C=V₂×(-3°C)
300ml×27°C/-3°C=V₂
8100ml/-3=V₂
-2700ml=V₂
or V₂= -2700ml
Which of the globes in Figure 7.9 will light up?
A tennis player hits a ball hard and 0.80 seconds later hears the echo from a wall. The speed of sound in air is 340m/s how far away is the player from the wall
Answer:
136 m.
Explanation:
From the question given above, the following data were obtained:
Time (t) = 0.80 s
Speed of sound (v) = 340 m/s
Distance (x) =?
The distance of the player from the wall can be obtained as follow:
v = 2x / t
340 = 2x / 0.80
Cross multiply
2x = 340 × 0.80
2x = 272
Divide both side by 2
x = 272 / 2
x = 136 m
Thus, the distance of the player from the wall is 136 m
4 A student says that he has made a magnetic field with some iron filings. What would
you say to him?
Answer:
Yes but no
Explanation:
Here the kid cant say that he has created s magnetic field as iron fillings do not have magnetic properties
Two manned satellites approach one another at a relative velocity of v=0.190 m/s, intending to dock. The first has a mass of m1=4.00×103 kg and the second a mass of m2=7.50×103 kg. If the two satellites collide elastically rather than dock, what is their final relative velocity?
Answer:
Their final relative velocity is 0.190 m/s
Explanation:
The relative velocity of the satellites, v = 0.190 m/s
The mass of the first satellite, m₁ = 4.00 × 10³ kg
The mass of the second satellite, m₂ = 7.50 × 10³ kg
Given that the satellites have elastic collision, we have;
[tex]v_2 = \dfrac{2 \cdot m_1}{m_1 + m_2} \cdot u_1 - \dfrac{m_1 - m_2}{m_1 + m_2} \cdot u_2[/tex]
[tex]v_2 = \dfrac{ m_1 - m_2}{m_1 + m_2} \cdot u_1 + \dfrac{2 \cdot m_2}{m_1 + m_2} \cdot u_2[/tex]
Given that the initial velocities are equal in magnitude, we have;
u₁ = u₂ = v/2
u₁ = u₂ = 0.190 m/s/2 = 0.095 m/s
v₁ and v₂ = The final velocities of the satellites
We get;
[tex]v_1 = \dfrac{2 \times 4.0 \times 10^3}{4.0 \times 10^3 + 7.50 \times 10^3} \times 0.095 - \dfrac{4.0 \times 10^3- 7.50\times 10^3}{4.0 \times 10^3+ 7.50\times 10^3} \times 0.095 = 0.095[/tex]
[tex]v_2 = \dfrac{ 4.0 \times 10^3 - 7.50\times 10^3}{4.0 \times 10^3 + 7.50 \times 10^3} \times 0.095 + \dfrac{2 \times 7.50\times 10^3}{4.0 \times 10^3+ 7.50\times 10^3} \times 0.095 = 0.095[/tex]
The final relative velocity of the satellite, [tex]v_f[/tex] = v₁ + v₂
∴ [tex]v_f[/tex] = 0.095 + 0.095 = 0.190
The final relative velocity of the satellite, [tex]v_f[/tex] = 0.190 m/s
What do is mean by environment friendly behaviour?
3 write the three laws given by kepler.How did they help Newton to arrive at the inverse square law of gravity?
Answer:
Kepler's laws apply: First Law: Planetary orbits are elliptical with the sun at a focus. Second Law: The radius vector from the sun to a planet sweeps equal areas in equal times. Third Law: The ratio of the square of the period of revolution and the cube of the ellipse semimajor axis is the same for all planets.
Answer me as much as you can
Answer:
b) Fluorescent powder.mention various medium level and higher level human resources related to engineering.
Answer:
Higher-level human resources related to engineering are those who:
Assist other engineers with solving complex problems. Work with management to keep the project on track. Mentor younger engineersMedium Level engineers will normally comprise the following:
They are responsible for developing engineering plans and performing calculations with respect to the same. Project workflow management Engineering Support facilitation Project Reporting Coordination of Team MembersCheers
A 15.0 cm object is 12.0 cm from a convex mirror that has a focal length of -6.0 cm. What is the height of the image produced by the mirror?
• -5.0 cm
• 7.5 cm
• -7.5 cm
• 5.0 cm
Answer:
5.0cm
Explanation:
To get the height of the image, we will use the magnification formula as shown:
m = Hi/H = v/u
Hi is the image height
H is the object height
v is the image distance
u is the object distance
First, we need to get the image distance v
Using the mirror formula;
1/f = 1/v+ 1/u
1/-6 = 1/v + 1/12
1/v = -1/12 - 1/6
1/v = -1-2/12
1/v = -3/12
v = 12/-3cm
v = -4cm
Next is to get the image height Hi
Using the expression;
Hi/H = v/u
Hi/15 = 4/12
Hi/15 = 1/3
3Hi = 15
Hi = 15/3
Hi = 5.0cm
Hence the image height is 5.0cm
Answer:
D. 5.0 cm
Explanation:
got it correct on the test
Pls help me with this fast. I will mark brainiest
Answer:
a) 70, 95
b) 95-70= 25cc
c) density= mass/volume
102/25
=4.08g/cc
Why does the weight of a body differ on different celestial bodies of the universe?
Multi-part question If a galaxy moving away from the Earth has a speed of 1000 km/s and emits 656 nm light characteristic of hydrogen (the most common element in the universe). What wavelength would we observe on the Earth
Answer:
658.2 nm
Explanation:
Since the galaxy is moving at relavitistic speed, we use the equation for relativistic Doppler shift of light.
So, the wavelength of light observed on the Earth is λ
λ = λ'([tex]\sqrt{\frac{ 1 + \frac{v}{c} }{1 - \frac{v}{c} } }[/tex])
where λ' = wavelength of light emitted by galaxy = 656 nm, v = speed of galaxy = 1000 km/s (positive since the galaxy is moving away from the Earth) and c = speed of light = 300000 km/s
So, substituting the values of the variables into the equation, we have
λ = λ'(√[{1 + (v/c)}/(1 - (v/c)]
λ = 656 nm(√[{1 + (1000 km/s/300000 km/s)}/(1 - (1000 km/s/300000 km/s)]
λ = 656 nm(√[{1 + 1/300}/(1 - 1/300]
λ = 656 nm(√[{(300 + 1)/300}/{(300 - 1)/300}]
λ = 656 nm(√[{(301)/300}/{(299)/300}]
λ = 656 nm(√[301/299])
λ = 656 nm(√1.0067)
λ = 656 nm × 1.0033
λ = 658.19 nm
λ ≅ 658.2 nm
So, the wavelength observed on Earth is 658.2 nm
Which of the following processes occurs in a battery?
Batteries convert mechanical energy into chemical energy.
Batteries convert chemical energy into kinetic energy.
Batteries convert mechanical energy into electric energy.
Batteries convert chemical energy into electric energy.
Answer:
Batteries convert chemical energy into electric energy.Explanation:
As seen, batteries have chemical energy in them stored which when used in any electronics produces electricity.
Thus, we can conclude that a battery converts chemical energy into electric energy.
A 250g object hangs from a spring that has a spring constant of 48.0 N/m and oscillates with an amplitude of 5.42cm
1)The magnitude of the objects acceleration when the displacement is 4.27 cm (down) is __ m/s^2
2)Given that the object has an amplitude of 5.42 cm the maximum speed that the object is __m/s
Explanation:
Given that,
Mass of an object, m = 250 g = 0.25 kg
Spring constant, k = 48 N/m
The amplitude of the oscillation, A = 5.42 cm = 0.0542 m
1. At equilibrium,
ma = kx
Where
a is the acceleration of the object
So,
[tex]a=\dfrac{kx}{m}\\\\a=\dfrac{48\times 0.0542}{0.25}\\\\a=10.4\ m/s^2[/tex]
2. The maximum speed of the object is :
[tex]v=A\omega\\\\v=A\sqrt{\dfrac{k}{m}}\\\\v=0.0542\times \sqrt{\dfrac{48}{0.25}}\\\\v=0.75\ m/s[/tex]
Hence, this is the required solution.
what you filling your heart with
oxygen and blood
Answer:
Explanation:
The right side of your heart receives oxygen-poor blood from your veins and pumps it to your lungs, where it picks up oxygen and gets rid of carbon dioxide. The left side of your heart receives oxygen-rich blood from your lungs and pumps it through your arteries to the rest of your body.
#I AM ILLITERATE
A 5.41 kg ball is attached to the top of a vertical pole with a 2.37 m length of massless string. The ball is struck, causing it to revolve around the pole at a speed of 4.75 m/s in a horizontal circle with the string remaining taut. Calculate the angle θ, between 0∘ and 90∘, that the string makes with the pole. Use g=9.81 m/s2.
Answer:
θ = 66º
Explanation:
This exercise of Newton's second law must be solved in part, let's start by finding the slowing down acceleration of the ball
a = v² / r
the radius of the circle is
sin θ = r / L
r = L sin θ
we substitute
a = v² /L sin θ
now let's write Newton's second law
vertical axis
T_y -W = 0
T_y = W
radial axis
Tₓ = m a (1)
let's use trigonometry for the components of the string tension
cos θ = T_y / T
sin θ = Tₓ / T
Tₓ = T sin θ
we substitute in 1
T sin θ = [tex]\frac{m \ v^2}{L \ sin \theta}[/tex]
T L sin² θ = m v²
we write our system of equations
T cos θ = m g
T L sin ² tea = m v²
we divide the two equations
L [tex]\frac{sin^2 \theta}{cos \theta}[/tex] = v² / g
(1 -cos²)/ cos θ = [tex]\frac{v^2 }{g \ L}[/tex]
1 - cos² θ = [tex]\frac{4.75^2}{9.81 \ 2.37}[/tex] cos θ
cos² θ + 0.97044 cos θ -1 = 0
we change variable cos θ = x
x² + 0.97044 x - 1 =0
x= [tex]\frac{-0.97 \pm \sqrt{0.97^2 - 4 1} }{2}[/tex]
since the square root is imaginary there is no real solution to the problem, suppose that the radius is 1 m r = 1 m
T sin θ = [tex]\frac{m \ v^2}{ r}[/tex]
T cos θ = m g
resolved
tan θ = [tex]\frac{v^2}{ r g}[/tex]
θ = tan⁻¹ ( 4.75²/ 1 9.81)
θ = 66º
What's an area of the earth that suggest that " the Earth is like one giant jigsaw" idea could be true.
Calculate the efficiency of the following appliances:
1. A radiator that converts 1000) of electrical energy into 900J
of heat energy and 100J of light energy
2. A torch that converts 100J of chemical energy into 35) of
light energy and 65J of heat energy
3. A car that converts 10,000J of chemical energy into 6000) of
kinetic energy and 4000J of heat energy.
4. An energy saver light converts 1,000J of electrical energy
into 7003 of light energy and 300J of heat energy.
5. A speaker converts 100J of electrical energy into 50J of
sound energy and 50J of heat and kinetic energy.
we
Answer:
1. The efficiency of the radiator is 90 %
2. The efficiency of the torch is 65 %
3. The efficiency of the car is 40 %
4. The efficiency of the energy saver is 70 %
5. The efficiency of the speaker is 50 %
Explanation:
Efficiency = (Useful energy out ÷ Total energy in) × 100 J
1. Useful energy = 900 J
The total energy in = 1000 J
The efficiency of the radiator = ((900 J)/(1,000 J)) × 100 % = 90 %
2. Useful energy = 65 J
The total energy in = 100 J
The efficiency of the torch = ((65 J)/(100 J)) × 100 % = 65 %
3. Useful energy = 4,000 J
The total energy in = 10,000 J
The efficiency of the car = ((4,000 J)/(10,000 J)) × 100 % = 40 %
4. Useful energy = 700 J
The total energy in = 1,000 J
The efficiency of the energy saver = ((700 J)/(1,000 J)) × 100 % = 70 %
5. Useful energy = 50 J
The total energy in = 100 J
The efficiency of the speaker = ((50 J)/(100 J)) × 100 % = 50 %
define inertia.mention it's types
Answer:
It is the inability of the body to change by itself its state of rest or uniform motion or direction. Types of Inertia- It is of three types-(1)Inertia of rest (2) Inertia of motion(3) Inertia of direction. (1) Inertia of rest - It is the inability of the body to change by itself its state if rest.
What is an effect of continental drift?
Answer: An effect of continental drift is causing tectonic plates resting upon the convecting mantle to move which results in natural disasters like earthquakes, volcanic eruptions, and more.
Why is velocity proportial to pressure?
Answer:
Pressure and velocity are inversely proportional to each other because if pressure increase, the velocity decrease to keep the algebraic sum of potential energy, kinetic energy and pressure constant.
A train travels 600 kilometers in 1 hour. What is the train's velocity in meters/second?
here's the answer to your question
Which court would you go to if you wanted to declare bankruptcy?
A.
Civil court
B.
U.S. Court of Appeals
C.
Supreme Court
D.
U.S. District Court
Answer:
A. Cilvil court.........
Civil court would you go to if you wanted to declare bankruptcy. The correct option is A.
Thus, According to the United States Bankruptcy Code, bankruptcy proceedings are typically filed in a federal bankruptcy court.
The federal court system includes these courts, which deal with Chapter 7, Chapter 11, and Chapter 13 bankruptcy cases.
The additional alternatives (U.S. Court of Appeals, Supreme Court, and U.S. District Court) are not the main courts where bankruptcy cases are generally filed.
Thus, Civil court would you go to if you wanted to declare bankruptcy. The correct option is A.
Learn more about Civil court, refer to the link:
https://brainly.com/question/29614273
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